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Question

A path \({1}{m}\) wide is built along the border and inside a square garden of side \({30}{m}.\) Find: (i) the area of the path (ii) the cost of planting grass in the remaining portion of the garden at the rate of \({R}{s}{40}\) per \({m}^{{2}}\)

Answer

With the given details, we can have two squares with \({1}\) m wide path.

The area of path will be the difference between these two squares area.

Please refer to video for the diagram of these two squares.

Side of outer square \(={30}{m}\)

Area of outer square \(={30}^{{2}}={900}{m}^{{2}}\)

Side of inner square \(={30}-{1}-{1}={28}{m}\)

Area of inner square \(={28}^{{2}}={784}{m}^{{2}}\)

So, required area of path \(={900}-{784}={116}\)m^2

The cost of planting grass in the remaining portion of the garden \(={784}\ast{40}={31360}\) Rs
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